The invention relates to a storage element including multiple lithium cells which are arranged adjacent each other as stack and are clamped to each other via end side arranged clamping plates which are connected to each other via clamping elements.
In the recent past storage elements including multiple lithium cells have become more and more important. The advantage of such lithium based storage elements is on one hand a high energy density, which can be stored or used. In addition such storage elements also deliver a very constant voltage, wherein the degree of self discharge is very low. They also display no memory-effect, i.e., they can be charged and discharged almost indefinitely.
As mentioned, such storage elements are configured from multiple individual cells which are ordered into stacks, and which are clamped to each other via corresponding clamping plates and clamping elements. The clamping of this cell block is necessary in order to achieve the desired service life. To this end prismatic cells are usually used, i.e., the storage element, be it a battery or an accumulator, is constructed type pure. Such prismatic cells consist of a strong, relatively rigid housing in which the actual storage unit is arranged. It thus consist of only one type of cells, the individual cells are connected in series and/or parallel. For some applications, for example when using such a storage element in a motor vehicle, mixed batteries, i.e., with two different types of cells present in the cell block, may be useful depending on the demands placed on the storage element. Especially useful would be the combination of prismatic cells and pouch cells, i.e., flexible cells often also referred to as “coffee-bag” lithium cells. These cells consist of flexible walls formed by a film, i.e., they are in themselves flexible. As a result, however, they cannot be integrated into a clamped cell block.